Semipositive clutch for spinning boxes



Jan. 16, 1951 I H. J. MCDERMOTT 2,538,258

SEMIPOSITIVE CLUTCH FOR SPINNING BOXES Filed Dec. 18, 1946 INVENTOR. AE/VRV J, McDERMOTT Patented Jan. 16, 1951 UNITED STATES PATENT OFFICE SEMIPOSITIVE CLUTCH FOR SPINNING BOXES Henry J. McDermott, Collingdale, Pa., assignor to American Viscose Corporation, Wilmington, DeL, a corporation of Delaware Application December 18, 1946, Serial No. 717,041

4 Claims.

, 1 This invention relates to centrifugal couplings which are of general utility for coupling a driving element with an element to be driven, such as two shafts in accordance with which a direct semi-positive coupling is obtained and the maximum power transmission obtained at any speed during which coupling is fully efiective is predetermined by the characteristics of the cou- I pling so that when the maximum load is eX- ceeded, as by braking, the driving mechanism is slowed down until the centrifugal action is ineffective whereupon the coupling slips thereby avoids damage thereto and without overloading the driving mechanism. The invention is hereinafter described in connection with rayon spinning buckets to which it is particularly applicable.

In the manufacture of rayon and the like, the thread or yarn is collected in a spinning bucket that is rotated at high speed by a drive shaft or motor spindle. It is the customary practice to place the buckets upon, and sometime to remove the buckets from, their drive spindles while the drive spindles are rotating at high speed. It istherefore, necessary that the spinning buckets be readily removable from the drive spindles. It is also necessary that the spinning bucket does not slip on its drive spindle during normal spinning operation.

Devices in the prior art depended on friction between the drive spindle and the spinning bucket to impart rotation to the spinning bucket. However, with this type coupling undue slippage, wear and vibration took place at higher speeds. This disadvantage of the prior art is overcome in the present invention.

The main object of the present invention is t provide improvements in means for coupling a spinning bucket to a drive spindle which will permit the spinning bucket to be readily applied thereto and also to be readily removed therefrom during rotation of the spindle and which assures substantially uniform speed of the spinning box during normal operation thereof for collecting yarns. Other objects and advantages of the invention will be apparent from the following description and following drawings.

In the drawings, a

Figure 1 is a sectional view of a spinning bucket embodying the invention,

Figure 2 is a sectional view taken on line II-II of Figure and Figure 3 is a modification of Figure 2.

Referring to the drawing, reference character 2 indicates generally a spinning bucket having 2 a hub portion 3 provided with a central bore. The spinning bucket, when in operative position, is mounted on the adapter bushing 5 which is rigidly attached to a motor spindle, not shown. While the bushing closely fits the upper portion of the central bore, sufficient clearance is provided to enable the spinning bucket to be readily removed and replaced on the adapter bushing.

An annular recess 6 is formed along a portion of the central bore and is adapted to contain two or more interfitting areuate shoes'l. The hub is countersunk at 8 to receive an annular plug 9 which may be threaded into the countersunk bore and serves to retain the shoes 1 loosely in the recess 6.

In the sectional view of Figure 2, the two shoes are of generally semi-circular form and their. abutting ends are of stepped form. This stepped interlock comprises an inner areuate projection 10 from the thick head I I, and having an inside cylindrical surface coincident with the rest of the shoe. The projection in is overlapped by an outer projection Illa on the tail l2 of .the adjacent shoe. The stepped interlocking .ends prevent the ends from projecting inwardly dur ing replacement of the bucket with its coupling upon the adapter bushing 5 which normally tightly fits the motor spindle and thereby such replacement is facilitated. To get a more positive drive at all speeds with a minimum of vibration, the projection Ill of each shoe slips into grooves or recesses l3 in the adapter bushing 5. There may be two or more grooves depending on the number of shoes used. However, as shown in the embodiment, there are two grooves employed. These grooves l3 are endmilled in an axial direction with the adapter bushing so as to form a ledge or the like for the shoes to push against, instead of relying on friction at this point to drive the spinning bucket.

If the shoes 1 should happen to be engaged in the grooves 13 at the time the spinning bucket 2 is withdrawn from the adapter bushing 5, they are pushed out of the way by the end radii of the. grooves l3.

The stepped form of the abutting ends may be omitted as shown in the modification in Figure-3." In this form of the invention the head portions I la and tail portions In of the arcuate shoes la abut against their respective plane surfaces as shown. By using a design of this type the machining operation in the manufacture of the shoes is minimized.

The", shoes have a thick head portion H bounded by concentric inside and outside surfaces of substantially cylindrical shape and inwardly tapering tail surface l2. As clearly shown in Figures 2 and 3, the inside and outside surfaces of the thick portion of each shoe have substantially the same radii as the adjacent surfaces on the driving element and the driven element 3 respectively. The relative are occupied by the thick head H and the tapered tail may vary widely. Preferably the tail constitute the major length of the shoe and as shown it occupies approximately 150 while the head (exclusive of the projecting step) extends 30. The outer surface of the tail may taper inwardly along any desired curve.

In operation it is preferable, though not absolutely necessary, that the tail 12 lead the head ll of a given shoe. Assuming this to be the case illustrated, rotation will be in a counterclockwise direction as viewed in Figure 2. During rotation, centrifugal force causes the tails l2 to swing outward. This pinches or wedges the heads ll between the grooves I3 in the adapter bushing 5 and the inwardly facing wall of the recess 6. This gripping of the grooves and frictional action between the shoes and spinning bucket increases with increase in speed of rotation. However, it is subject to slipping without damaging the cooperating parts when overloading occurs. The force exerted by the gripping and wedging action may be varied, if desired, by increasing or reducing the weight of the tail I2.

.While preferred embodiments have been shown, it is to be understood that changes and variations may be'made without departing from the spirit and scope of the invention as defined in the appended claims.

I claim:

1. In combination, a driving element rotatable on an axis and having an outwardly facing concentric annula surface with at least two axial grooves therein, a driven element having an inwardly facing annular surface concentric with, andhaving a larger diameter than, that of the driving element thereby providing an annular space between the two surfaces, and means for 45 coupling said driven element to the driving element consisting of a plurality of arcuate shoes disposed in the space, each of the shoes having a thick portion, of which both inner and outer surfaces have the axis of the driving element as a common center and have a running fit adjacent the two engaging surfaces of the elements, and a tapered portion having as its inner surface an arcuate extension of the inner surface of the thick portion with the same radius and having its outer surface tapering inwardly and eccentric to the inner surface, each shoe being movable in response to centrifugal force to swing the tapered portion outwardly and to wedge the thick portion into gripping engagement with the two engaging surfaces of the elements and into gripping engagement with one of said axial grooves in the driving element.

2. The combination of claim 1 in which the thick end of one shoe is disposed adjacent the end of the tapered portion of the adjacent shoe.

3. The combination of claim 2 in which both ends of each shoe are stepped to provide interlocking engagement of the ends of adjacent shoes.

4. The combination of claim 3 in which a circumferential projection from the inner portion of the thick end of each shoe is disposed inwardly of, and in overlapping relation to, an oppositely extending projection from the outer portion of the end of the tapered portion of the adjacent shoe.

HENRY J. McDERMOI'I.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 684,478 Trimble Oct. 15, 1901 1,082,657 Smith Dec. 20, 1913 1,383,221 Lombard June 28, 1921 1,958,884 Bonanno May 15, 1934 2,108,105 Cotterman Feb. 15, 1938 2,224,935 Schultz Dec. 17, 1940 FOREIGN PATENTS Number Country Date 441,436 France May 24, 1912 587,112 France Apr. 11, 1925 

